Dry cutting technology: principles, advantages and application prospects

I. Concept and Principle of Dry Cutting Technology

Dry cutting technology is a machining method that completely eliminates the need for cutting fluid. It replaces the cooling, lubrication, and chip removal functions of cutting fluid through the coordinated action of the tool, machine tool, and process. Traditional wet machining relies on cutting fluid to reduce temperature during the cutting process, minimize tool wear, and aid in chip removal, but dry cutting technology breaks this model. In dry cutting, air cooling or minimum quantity lubrication (MQL) is typically used, which involves applying a small amount of lubricant or air spray to lubricate and cool the cutting tool and workpiece.

The core of dry cutting technology lies in utilizing advanced tool materials and designs, optimized machine tool structures, and rational machining processes. For example, using highly wear-resistant tool materials, such as PCBN tools (temperature resistance up to 2000℃) and TiAlN-MoS₂ coated tools, allows these tools to withstand higher cutting temperatures and extends tool life. Simultaneously, machine tool designs incorporating technologies such as vacuum chip removal and graphene heat dissipation modules effectively reduce the temperature in the cutting zone. In terms of process technology, high-speed cutting (1200 m/min) combined with five-axis linkage and other technologies improves machining efficiency.

II. Advantages of Dry Cutting Technology

(a) Cost optimization

1. Direct cost reductionDry cutting technology completely eliminates the use of cutting fluid, directly saving on expenses related to coolant procurement, storage, and waste disposal. Taking semiconductor ceramic substrate processing as an example, in traditional wet machining, cutting fluid costs account for 18%-22% of the total processing cost, while dry technology can reduce this cost to zero. Furthermore, using highly wear-resistant cutting tools, such as silicon carbide tools, with a lifespan more than five times that of traditional tools, reduces tool replacement frequency by 60% and annual consumable costs by 35%.
2. Reduced energy consumptionDry cutting eliminates the need for a coolant circulation system, reducing equipment energy consumption. For example, in the machining of silicon nitride turbine blades, spindle power consumption drops from 8.5kW in wet machining to 6.2kW, and combined with a vacuum chip removal system, overall energy efficiency is improved by 30%. Furthermore, the absence of cutting fluid residue prevents corrosion of machine tool guideways and lead screws, extending equipment maintenance intervals from 200 hours to 500 hours, and reducing lubricant consumption by 40%.
3. Improved material utilizationThrough micron-level cutting control and intelligent compensation algorithms, material utilization has been increased from 65% in traditional processes to over 90%. In the processing of zirconia crowns, material loss per piece has been reduced from 3.2g to 0.8g.

(ii) Environmentally friendly

1. Reduce pollutionDry cutting does not produce wastewater or harmful fumes, avoiding the environmental pollution caused by coolant during wet machining. At the same time, chip cleanliness reaches over 95%, increasing recycling value by 20%, which is beneficial for resource recycling.
2. Meets environmental standardsGreen cutting technology encompasses a complete system of technologies including "liquid-free/liquid-reduced machining + energy saving and consumption reduction + waste resource utilization". Dry cutting, as an important component, helps to reduce energy consumption by 15% - 30% and waste liquid by more than 90%, meeting the ISO14001 standard.

(III) Improve processing quality

1. Improve visibilityDry machining improves workpiece visibility, making it easier for operators to detect problems and monitor work quality.
2. Reduce post-processing stepsBecause there is no coolant or lubricant in contact with the workpiece, there is almost no need for post-machining cleaning or degreasing, which simplifies the production process.

III. Key Technology System of Dry Cutting Technology

(a) Tooling System

Cutting tools are a key factor in dry cutting technology. PCBN tools possess high hardness, high wear resistance, and high temperature resistance, withstanding temperatures up to 2000℃. They maintain excellent cutting performance in dry cutting, extending tool life by 2-5 times. TiAlN-MoS₂ coated tools also effectively improve wear resistance and anti-adhesion properties, reducing friction between the tool and workpiece, thereby improving machining quality and tool life.

(II) Machine Tool Design

1. Vacuum chip removalThe vacuum chip removal system can remove chips from the cutting zone in a timely manner, preventing chip accumulation from affecting the machining process and reducing the generation of cutting heat.
2. Heat dissipation moduleUtilizing advanced technologies such as graphene heat dissipation modules, the cutting zone temperature can be effectively reduced by 40-60℃, ensuring the stability and precision of the machining process.

(III) Process Optimization

1. High-speed cuttingHigh-speed cutting (1200 m/min) can improve material removal rate, reduce cutting force and heat generation, and increase machining efficiency. For example, in silicon carbide machining, the use of high-speed cutting combined with five-axis linkage technology can increase machining efficiency by 5 times.
2. Intelligent regulationBy utilizing intelligent compensation algorithms and digital twin technologies, the cutting process is monitored and adjusted in real time to ensure machining accuracy and quality.

IV. Application Scenarios of Dry Cutting Technology

(I) Automobile Manufacturing Sector

1. Gear machiningThe machine adopts a permanent magnet spindle and dry cutting technology, which saves 8,600 kWh of electricity per unit per year, reducing production costs while improving processing efficiency and product quality.
2. Motor end cover processingIt replaces emulsions for dry cutting, reducing waste liquid by 12 tons per year and saving 80,000 yuan in wastewater treatment fees, achieving a win-win situation for both environmental protection and economic benefits.

(II) Aerospace Field

1. Titanium alloy parts machiningThe dry cutting technology, which adopts MQL + AI parameter optimization, reduces energy consumption by 18% and achieves an accuracy of 0.01mm, meeting the high precision and high performance requirements of the aerospace industry for parts.
2. High-temperature alloy processingLiquid nitrogen cooling combined with dry cutting increases tool life by 3 times, improving machining efficiency and tool lifespan.

(III) Field of hard and brittle materials

1. Ceramic filter processingThe dry + ultrasonic assisted cutting technology can achieve a hole diameter accuracy of 0.1mm ±2μm and an edge chipping rate of <0.2%, ensuring the processing quality of ceramic filters.
2. Semiconductor wafer processingDry cutting reduced the cost per unit from 280 yuan to 95 yuan, lowering production costs and enhancing the competitiveness of the semiconductor industry.

V. Challenges Facing Dry Cutting Technology

(a) High initial equipment investment

Dry cutting technology requires advanced cutting tools, machine tools, and processes. The cost of upgrading a single piece of equipment is between 20,000 and 30,000 yuan. For small and medium-sized enterprises (SMEs), the initial investment is high, and the payback period is relatively long. Although SMEs can recoup their investment in 6 months and generate an annual profit of 120,000 yuan, the initial financial burden remains a challenge.

(ii) Heat dissipation problem of difficult-to-process materials

For some difficult-to-machine materials, such as Inconel 718, heat dissipation is challenging during dry cutting, easily leading to excessively high workpiece and tool temperatures, affecting machining quality and tool life. Therefore, it is necessary to develop composite cooling technologies, such as MQL + cryogenic cooling, to solve the heat dissipation problem.

(III) Technological Bottlenecks

Low-temperature cutting can easily lead to microcracks in workpieces, necessitating further research and development of new cooling technologies and processes to avoid impacting workpiece quality. Simultaneously, continuous improvement in tool materials and coating technologies is required to meet the demands of dry cutting.

VI. Future Development Trends of Dry Cutting Technology

(I) Intelligent Integration

Digital twin technology can be used to predict carbon emissions (with an error of < 5%), helping companies better control the environmental impact of their production processes. AI technology can provide 72-hour advance warnings of equipment failures, enabling preventative maintenance and improving production efficiency and reliability.

(II) Breakthrough in Composite Technologies

Laser-assisted dry cutting technology can increase material removal rate by 200%. Through the energy of the laser, the material is softened, cutting forces are reduced, and processing efficiency is improved. Furthermore, dry cutting can be combined with other processing technologies, such as ultrasonic vibration cutting, to further improve processing quality and efficiency.

(III) Zero-carbon manufacturing

By adopting photovoltaic power supply and waste heat recovery technology, a "self-circulating" green workshop is constructed to achieve energy self-sufficiency and recycling, reduce dependence on traditional energy sources, reduce carbon emissions, and meet the requirements of sustainable development.

Dry machining technology, as a green and efficient processing technology, offers significant advantages in cost, environment, and machining quality. Although it currently faces some challenges, its application prospects will become even broader with continuous technological development and innovation. Enterprises should actively monitor the development trends of dry machining technology and, in conjunction with their own needs, gradually promote and apply this technology to enhance their competitiveness and sustainable development capabilities.